The Dimensional Stability of Acrylic Knit Fabrics

Fabrics knit from three different stable acrylic yarns have been examined for dimen sional stability both in the dry relaxed form and with length distortion. Three methods of wet relaxation were employed: wetting and drying at 115°C, immersion in boiling water, and tumble drying. While acrylic knit goods are similar to comparable goods knit from cotton or wool with respect to wet relaxation shrinkage, two important differences are demonstrated. First, the minimum temperature at which relaxation shrinkage occurs is well above room temperature. Secondly, the equilibrium loop shape is shown to be a function of the thermal history of the fabric.